I've been watching videos of where they're collected, they are ALWAYS above the green ones. The red coloration is like sunscreen for them, filtres out the intensity. Don't make me come down there and take you out on the reef and show you first hand because I will!! :D Watch videos on youtube, that's what I do all the time if I run into a problem. Wish we had that back in the day, I wouldn't have killed so many specimens. :( Also, boron apparently is something the red coloration uses up a lot of. My Blastomussa was getting pale, started dosing borochrome and he's coming back quite nicely.
